The term communication services is meant to mean conventional telephony services, telex services, datapack services, datel services, telefax services, videotext services, ISDN-services, mobile telephony services, personal paging services, tele-point-services and general communication between two or more parties. The services recited above are only examples of the services possible and are not intended to limit the scope of the invention.
The term telecommunication network is normally meant to mean the telephone networks, telex networks, circuit connected data networks, picture information transfer networks, private telecommunication networks, radio networks, satellite communication networks and general carriers of the communication services, such as analog transmission, digital transmission, synchronous, multiplex or asynchronous multiplex transmission, ATM, etc., for example. These networks are recited solely by way of example and the invention is not restricted thereto.
The term functionality is meant to mean the ability to perform an operation in a telecommunication network. Examples of functionality include activities and services that can be performed in the telecommunication network. Examples of functionalities include an enquiry to establish a connection path or route between two parties, digit analysis, billing or ticketing. Although not necessary, the functionality may require the availability of dedicated equipment for carrying out the functionality. For instance, if the functionality is to receive tones and to analyze tones, it is necessary to make a tone receiver accessible. Other examples of functionalities include voice-controlled speech information, number translation service, conference calls. Other examples of functionality include the functionalities described in the aforesaid five Swedish patent applications, namely communication in the form of a meeting, personal paging, a method of establishing cooperation with a functionality, meeting connection establishment and communication via intermediaries. Still another example of functionality is the ability of being able to choose from among several alternatives.
The term connection is meant to mean a circuit-coupled connection or a package-coupled connection. The term to establish a connection is meant to mean in the circuit coupled case that a circuit-coupled connection is established between two hardware terminal devices (or equipment) and in the package coupled case it is meant that a package-coupled connection creates relationships between logic channels on node-interconnecting physical links which. The term to originate or to terminate a connection, is meant to mean in the circuit-coupled case to connect originating or terminating equipment to a circuit-coupled connection, and in the package-coupled case to create a session between applications in originating and terminating nodes respectively.
The term user is meant to mean in the following a human user or a computer-based application which utilizes communication services. The application may be achieved with hardware, software and combinations thereof. The word "part" is synonymous to the term user.
The term terminal is meant to mean equipment which is connected to a telecommunication network and which makes the telecommunication services of the network available to a user.
The term port either refers to an access port or to a transit port. An access port is a location where a dedicated terminal is connected to a telecommunication network. An access port is associated with a destination address which goes to an end user. In the case of a standard telephone network, the access ports are located in a telephone station. In the case of the ISDN-network and the mobile telephone network, the access ports are found in a terminal. A transit port is a port in a connection between nodes. A transit port is not associated with any particular destination address, and can be used to establish any selected connection with a final destination. The final destination is given by the destination address. A transit port can transfer a call to another node or can receive a call from another node.
The final destination of a call is a terminal which is identified by a destination identity. The terminal can be present in the same node as a transit port or in some other node to which the call shall be further connected.
One fundamental feature of present-day communication services is that when a party, hereinafter called A, wishes to communicate with another party, hereinafter called B, A sends a call to B, whereupon a connection is established between A and B. The call and the establishment of a connection route is a coupled sequence. By this is meant that the information which A uses in the call, namely information relating to the identification of B's access point in the telecommunication network, causes a connection route, or path, to be established between the parties. This connection can either be circuit-coupled or, in the case of non-continuous transmission methods, a so-called virtual connection, e.g. a package-coupled network, ATM-network (Synchronous transfer mode), etc. Traditionally, a connection is established by establishing a route from an origin to a destination. The connection route through the telecommunication network is controlled by fixed, so-called routing tables which are drawn up when configuring or reconfiguring the network. The routing tables may sometimes permit alternative selections, based on local accessibility information.
The traditional communication network is encumbered with many drawbacks. A first problem concerns handling of the resources of the communication network. Firstly, the communication network is, in itself, a resource which is utilized uneconomically in the traditional method of providing communication services. For example, when party A calls party B, so as to establish a connection through the network from A to B, and party B does not accept the call, the network resources have been used unnecessarily. The same applies when party B is engaged. The case is dependent on the predominant use of present-day networks of channel-associated signalling. This involves establishing a signalling connection, which is then used for speech purposes. With common channel-signalling, which is used primarily in the long-distance network, the signal connection is established with the aid of the data package, or packet, whereas the speech connection, the expensive part of the communication, is not established until B answers. Common channel-signalling is scarcely used in local networks. Secondly, the majority of all established connections do not require party B to act immediately on the information that A will transfer.
In the aforesaid cases, the network resources are either used unnecessarily or are utilized in real time, although it would be possible to utilize the resources at a later time.
Present-day telecommunication services do not enable a party A to call a party B on a telecommunication network and establish communication with party B on a telecommunication network which is different to the first-mentioned network. If the party B has access points in several different telecommunication networks, it is necessary for the party A to have knowledge of all these access points in order to be able to utilize alternative methods of communicating with party B. If party B does not answer in one telecommunication network, it is necessary for party A to attempt to reach party B in another communication network. This means that it is necessary for party A to call on network after network before finally reaching party B. Furthermore, it is also necessary, of course, for party A to have in his/her possession a list of party B's access ports in the different networks at the disposal of party B.
Traditionally, a connection is established between two parties by a party who wishes to communicate with the other party making a call and giving the call destination address, whereafter a coupling route to the called party is established from node to node in a telecommunication network, until the destination node is reached. The calling party is connected to the called party at the destination node. In conventional telecommunication networks, the connection route follows fixed, predetermined routing tables. These routing tables are very seldom changed, and then normally only when extending the telecommunication network. The principle of establishing a connection with the guidance of routing tables is encumbered with several drawbacks.
A first drawback is evident from the following discussion. Two parties who wish to communicate with one another are located at widely separated places in a telecommunication network. When the connection route is established from the calling party, wherein the connection passes from node to node inwardly towards the center of the network, there are many different possibilities of choosing routes to the destination node. The more connection routes that thereafter pass from the center of the network out towards the destination node, the fewer the possibilities of choosing a route to the destination node. Thus, although many routing possibilities are found in towards the center of the network, the routing possibilities outwards from the center of the network become fewer and fewer. This is a drawback in itself. The trunk line on which the discussed connection arrives at the destination node may be congested or blocked while trunk lines in this same destination node are idle. Because of the routing tables, however, these idle trunk lines cannot be placed at the disposal of telephone calls in the direction from which the user connection route arrives at the destination node.
Another drawback with establishing the connection from the node of the called party to the destination node, by switching from node to node through the network in accordance with fixed routing tables, occurs when a node has a fault or is congested, so as to necessitate reversing the route in the network in order to reach a new node and to establish therefrom a new route which will circumvent the obstacle. The routing tables are therefore particularly comprehensive and, above all, categoric, i.e. rigid, and cannot therefore be adapted to current traffic situations.
A large sporting event of a temporary nature is another situation in which blocks can occur in a node. Under such circumstances, there is a very great need for communication from the local node that serves the area or region in which the sporting event takes place. The public, press, radio and television load both the local telephone station and the mobile radio base station serving the area or region in which the sporting event takes place. Blocks occur on the trunk lines to and from the local station/mobile base station, although it may still be possible to establish connections with adjacent local nodes from which it should be possible to establish connections. This is not always possible, however, because of the fixed routing tables.
The application WO-A1-92/01350 relates to a communication arrangement using a callback feature. The originator of a call places a first call to an intermediary, then the originator sends target-identifying information, for example, the telephone number, including relevant country and/or area codes, to the intermediary. The originator also identifies himself to the intermediary. Then the originator hangs up. The intermediary then places a second call to the target, using the target-identifying information, and a third call, the call-back, to the originator, using the originator-identification. When the target answers and the originator answers the second and third calls are interconnected, thus establishing a communication path between the originator and the target.
The drawback with this communication arrangement is that the originator has to use special call routine, differing from the normal call routine, when he wants to use the communication arrangement. First, he must dial a predetermined number, the one to the intermediary, then he must give the target identification, then his own identification, then he must hang up and wait for the call-back from the intermediary. Also the intermediary has to follow a strict procedure in order for the communication arrangement to operate.
This is in contrast to the present invention in accordance with which the originator dials the telephone number to the target in the usual manner and the telephone network, not the originator, uses a special communication arrangement, differing from the known described above, in order to establish communication between the originator and the target.
In accordance with a fifth embodiment of the invention according to the aforesaid WO-A1-92/01350; the first call is parked at a first intermediate after the originator has supplied the target-identifying information. This information is communicated to a second intermediate, situated close to the target. The second intermediator places a second call to the target and a third call, the call-back, to the first intermediator holding the parked first call. When the second call is answered by the target the second and third calls are interconnected and simultaneously the third call is interconnected with the first parked call.
In accordance with this fifth embodiment, the originator does not need to hang up awaiting the connection with the originator. However, the originator has to follow a very specific procedure, different from that used when making a call in the normal manner, which is awkward.
The manner in which the third call is interconnected with the parked first call is not disclosed by the patent specification and poses a technical problem in that the first intermediate cannot differ between an incoming call from the target and an incoming call from anyone else dialling the originator's telephone number.
The main purpose of the communication arrangement in accordance with the application WO-A1-92/01350 is to reduce the costs of a call. If it is cheaper to make a call from e.g. U.S.A. to France than to make the same call from France to U.S.A. then the intermediate is located in the U.S.A. and is used by French originators. If the situation is reversed, i.e., it may for example be cheaper to call from France to the U.S.A. during nighttime in the France, then an intermediate is located in France and is used by U.S. originators. In order to benefit from this known communication arrangement the parties themselves must keep track of the taxes used by the French, and U.S. telephone network operators. In other words an originator must not only use a different communication procedure but must also know if a French or a U.S. intermediate should be called. The situation gets more and more complex as the number of states gets larger.
In accordance with applicant's invention, the network and not the individual keeps track of the taxes and instructs either the originator to make a call to the target or the target to make a call to the originator or instructs both parties to make a call to a common telephone number belonging to a telephone station somewhere between the originator and the target. The network makes its decisions not only with regard to the lowest call cost but also with regard to using the available network resources in the most efficient way. All decisions are taken on a dynamic basis, meaning that the procedure to follow for a specific call may vary depending on traffic intensity, taxes, trunks that are available etcetera., at the time the call is to be setup between the originator and the target. The communication arrangement according the application to WO-A1-92/01350 uses the originators telephone number as originator-ID and the target's telephone number as target-ID. The two ID:s are used only for the purpose of placing a call. In accordance with applicant's invention special numbers, called IA-numbers, connected to a telephone station are used for several purposes amongst them for placing a call between two parties, for selecting the route of a call as taught by the present invention, for supporting communication between a master and foreign users via an intermediator as taught by our co-pending U.S. patent application Ser. No. 08/018,215, for implementing various services such as 800-services as described in our co-pending U.S. patent application Ser. No. 08/018,197.